Fix smbdirect_map_sges_from_iter() to use pre-decrement, not post-decrement
so that it cleans up the correct slots.

Fixes: e5fbdde43017 ("cifs: Add a function to build an RDMA SGE list from an iterator")
Closes: https://sashiko.dev/#/patchset/20260326104544.509518-1-dhowells%40redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <sfrench@samba.org>
cc: Stefan Metzmacher <metze@samba.org>
cc: Paulo Alcantara <pc@manguebit.org>
cc: Tom Talpey <tom@talpey.com>
cc: linux-cifs@vger.kernel.org
cc: linux-fsdevel@vger.kernel.org
---
 fs/smb/smbdirect/connection.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/smb/smbdirect/connection.c b/fs/smb/smbdirect/connection.c
index fe9912e53da6..8adf58097534 100644
--- a/fs/smb/smbdirect/connection.c
+++ b/fs/smb/smbdirect/connection.c
@@ -2168,7 +2168,7 @@ static ssize_t smbdirect_map_sges_from_iter(struct iov_iter *iter, size_t len,
 
 	if (ret < 0) {
 		while (state->num_sge > before) {
-			struct ib_sge *sge = &state->sge[state->num_sge--];
+			struct ib_sge *sge = &state->sge[--state->num_sge];
 
 			ib_dma_unmap_page(state->device,
 					  sge->addr,

Am 13.05.26 um 20:50 schrieb David Howells:
> Fix smbdirect_map_sges_from_iter() to use pre-decrement, not post-decrement
> so that it cleans up the correct slots.
> 
> Fixes: e5fbdde43017 ("cifs: Add a function to build an RDMA SGE list from an iterator")
> Closes: https://sashiko.dev/#/patchset/20260326104544.509518-1-dhowells%40redhat.com
> Signed-off-by: David Howells <dhowells@redhat.com>
> cc: Steve French <sfrench@samba.org>
> cc: Stefan Metzmacher <metze@samba.org>
> cc: Paulo Alcantara <pc@manguebit.org>
> cc: Tom Talpey <tom@talpey.com>
> cc: linux-cifs@vger.kernel.org
> cc: linux-fsdevel@vger.kernel.org

Reviewed-by: Stefan Metzmacher <metze@samba.org>

Thanks!
metze

> ---
>   fs/smb/smbdirect/connection.c |    2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/smb/smbdirect/connection.c b/fs/smb/smbdirect/connection.c
> index fe9912e53da6..8adf58097534 100644
> --- a/fs/smb/smbdirect/connection.c
> +++ b/fs/smb/smbdirect/connection.c
> @@ -2168,7 +2168,7 @@ static ssize_t smbdirect_map_sges_from_iter(struct iov_iter *iter, size_t len,
>   
>   	if (ret < 0) {
>   		while (state->num_sge > before) {
> -			struct ib_sge *sge = &state->sge[state->num_sge--];
> +			struct ib_sge *sge = &state->sge[--state->num_sge];
>   
>   			ib_dma_unmap_page(state->device,
>   					  sge->addr,
>